Inflight coffee and tea are traditionally brewed using the airplane's internal water tanks, which are notoriously difficult to clean and frequently test positive for various delightful strains of coliform bacteria.

A closer look

Inflight coffee and tea are traditionally brewed using the airplane's internal water tanks, which are notoriously difficult to clean and frequently test positive for various delightful strains of coliform bacteria. Flight attendants routinely refuse to drink the hot beverages they serve you because they know those holding tanks are often parked directly next to the lavatory waste systems and are serviced by the exact same ground crews using highly questionable sanitation protocols. Enjoying a warm cup of Earl Grey at thirty thousand feet is basically just a fun immune system stress test, heavily disguised by a thin layer of artificial creamer and your own crushing desperation for caffeine during a miserable transcontinental red eye flight